Private Temporary Tables in Oracle Database 18c
Oracle 18c introduced the concept of a private temporary table, a memory-based temporary table that is dropped at the end of the session or transaction depending on the setup.
If you’ve come to Oracle from a different database engine, like SQL Server, you might be confused by Oracle’s idea of temporary tables. In SQL Server developers will regularly create a temporary table to do some work and drop it. In Oracle a Global Temporary Table (GTT) is a permanent metadata object that holds rows in temporary segments on a transaction-specfic or session-specific basis. It is not considered normal to create and drop GTTs on the fly. With the introduction of private temporary tables, Oracle has an option similar to that seen in other engines, where the table object itself is temporary, not just the data.
Posted from: https://oracle-base.com/articles/18c/private-temporary-tables-18c
Which two statements are true about space-saving features in an Oracle Database? (Choose two.)
- A. Private Temporary Tables (PTTS) store metadata in memory only
- B. An index created with the UNUSABLE attribute has no segment
- C. If they exist for a session, Private Temporary Tables (PTTs) are always dropped at the next COMMIT OR ROLLBACK statement
- D. An index that is altered to be UNUSABLE will retain its segment
- E. A table that is truncated will always have its segment removed